1. Field of the Invention
The present invention relates to an actuator control system adapted to carry out positioning control of an object under control by moving the object in two axial directions by means of an actuator provided for each axis.
2. Description of the Related Art
As a mechanism for moving an object under control by moving it in two axial directions by actuators to position the object, there has been known, for example, an automatic/manual transmission (automatic MT) that includes actuators, such as motors, to replace a manual transmission that performs selecting and shifting operations to transmit motive power between an input shaft and an output shaft of a vehicle by driver's manual selecting or shifting operations.
The present inventors have proposed a control system for performing a shifting operation of an automatic/manual transmission by adopting a response specifying control in the previous application, namely, Japanese Patent Laid-Open Publication No. 2004-211717. In the control system, a coupling sleeve that integrally rotates with an input shaft is moved into contact with a synchronized gear through the intermediary of a synchronizer ring, and the coupling sleeve and the synchronized gear are rotationally synchronized to perform shifting operations.
In this case, the response specifying control is conducted by determining a manipulated variable for driving actuators so as to converge the value of a switching function to zero. The switching function is defined by a linear function based on the difference of a target position and an actual position of a coupling sleeve. A computing coefficient of the linear function is set to lower disturbance suppressing capability level so as to produce a compliance property, which is resiliency of, for example, rubber, thereby damping contact impacts when the coupling sleeve comes into contact with the synchronizer ring.
In the positioning control of a control object in two axial directions, when the control object is to be moved toward a target position on one axis while the control object has been positioned at a target position on the other axis, the movement toward the target position is obstructed if an interfering object exists on the movement path. This prevents the control object from being moved to the target position and also causes overload on the actuators.